not a synspilum! i had many of them it aint one. i also had Guttatlatus, Fenestratus, Hartweegi and Maculicauda, so i have qa lil bit of experince with Vieja. i personally put my money on Fenestratus. i think this because of the purlpeish head, body shape, head shape and the black on the sides.
will be an aggressive fish, get about 12inch, but very colourful. nice one mate, keep up the good stuff.